At the beginning of the offseason, the White Sox had three men on their roster who had at one time been the team’s closer for an extended period of time. Chris Sale was nearly unhittable at the end of the 2010 season, but he’s moving into the Sox’s rotation. Sergio Santos, in just his third season as a pitcher after converting from shortstop in the minors, saved 30 games in 2011 and got a ticket to Toronto for his troubles. That leaves Matt Thornton, whose turn as a closer early last season can charitably be described as unsuccessful, as the man most likely to get the ball with the team up three or fewer runs in the ninth.

New manager Robin Ventura confirmed that Thornton had the inside track to the closer’s job in late January, and while things might change between then and Opening Day, it’s looking more and more like Ventura is putting owners in a “once bitten, twice shy” position as Thornton’s previous stint as the White Sox closer left owners with just three saves and terrible peripherals to show for their troubles.

His overall numbers weren’t great, but they belie his performance as the team’s closer. For the whole of 2011, Thornton posted a 3.32 ERA and a 1.36 WHIP with 9.5 K/9, which aren’t superb numbers, but certainly aren’t bad enough to warrant the kind of invectives that were being thrown around by callers on Chicago’s sports stations after his performance. More to the point, in 28 save situations, Thornton allowed 14 runs — though just 8 were earned — and had a 1.48 WHIP, but even that doesn’t quite explain why more than three-quarters of respondents in a CSNChicago poll wanted someone not named Thornton to close for them. Thornton’s reputation as a closer stems largely from the first week of the season, as in his seven appearances before losing the closing job to Santos, the Sox went 1-6, Thornton blew four saves, posted a 6.75 ERA and a 2.40 WHIP, and allowed opponents a .998 OPS. He did not pitch well during that stretch, but his collapse wasn’t solely one of his own making, as the White Sox defense did him slight on no fewer than three occasions.

I will confidently assert that Thornton’s 2012 won’t start as badly as his 2011 was, but that doesn’t mean he’ll pitch well enough to keep the job. If he founders again, Thornton won’t be the first middle reliever not to make the transition to closer with ease. Additionally, this is Thornton’s age-35 season, and while age doesn’t weigh as heavily on relievers as it does on position players, the White Sox can’t be blamed for preparing for the eventuality that they won’t have Thornton around. As much as I think the Sox should be turning to Sale as their closer of the future, they seem determined to put him in the rotation, making 2010 third round pick Addison Reed the likely closer of the future and the man to pair with Thornton in the short term.

Unlike Sale, who started for two full years in college — though he didn’t rack up a particularly high number of innings in that role — Reed was almost exclusively a reliever, having started just 11 total games since 2008. He rose exceptionally quickly through the minors, playing at five levels last year from Low-A all the way up to a cameo with the big club. It’s a testament to his polish, that much is sure, but with no more than 28.1 innings at any given level, it’s hard to make substantive judgments about his potential ability to handle major league competition in 2012. Two things were consistent at all five levels, however: Reed strikes out a lot of hitters and he walks very, very few. If I’m picking two qualities for a high-leverage reliever, those two are it, and that gives me faith that he’ll be an effective major leaguer when he gets his chance. He maintained a 0.73 WHIP in the minors last year over the course of 43 appearances, and while it rose to 1.50 in the majors, it’s not hard to believe that fatigue played a role in that jump as well as the obvious increase in the quality of opposition.

I see three reasons that Reed may not get the closer’s job this year, even if Thornton falters. First, while he did dominate in Triple-A for the 11 games he was there, the Sox may want to see if he can do the same over a longer period of time. Pitchers have a big advantage over hitters when the pair haven’t faced before, and very few hitters saw Reed more than once. This isn’t to say that his numbers are a mirage or figment, but they may look less like video game numbers as the playing field tilts less in his favor.

Second, if the White Sox don’t get off to a great start, there will be an incentive for them to keep Reed in the minors to keep his service clock from running. The new CBA changed the amount of time Reed would need to spend in the minor in order not to be a Super Two, but the possibility still exists. If the Sox are playing well, they may need Reed to help shore up a bullpen that is missing two of its key members from last year. If he dominates Triple-A, it will be harder to keep him out of the majors, but any regression strengthens the White Sox case that the 23-year-old could use more time outside of the majors.

The last thing that might keep Reed from succeeding Thornton as the closer is something of a long shot, but worth keeping in mind. While the Sox are committed to Sale in the rotation, I have serious concerns about his ability to stick there. He has never thrown more than 140 innings in a season, which increases the likelihood that he’ll run into fatigue issues either this year or next year. Additionally, while his stuff is good, there’s no doubt in my mind that his atypical delivery helps him fool hitters. Increased exposure will limit that advantage for him. Redraft players have less to be concerned about, as I’d be very surprised if the White Sox don’t give Sale a full year to show what he can do in the rotation, but keeper league players ought to be at least aware of the possibility that Sale — though he’s slated for the rotation now — may find his way back into the bullpen between the 2012 All-Star Game and Opening Day 2013. Who gets the saves when both Reed and Sale are potential options is anyone’s guess.

Even with those concerns, Reed should be a late round pick for anyone considering Thornton in all but extremely shallow leagues. Like Vinnie Pestano, whom I covered on Tuesday, even if Reed doesn’t get saves, he should give owners a goodly number of strikeouts with usable peripherals. Adding to Reed’s profile is the fact that Ventura hasn’t named his closer yet. I fully expect Thornton to be the man at least for the first few weeks of the season, but there is a chance Reed could win the job with a stellar camp. Even if he doesn’t leave Arizona with the job, Reed will almost certainly get his shot by the end of the season.